I'm not sure if I can help, cause don't have many experience with lights, but anyway I'd start debugging things in that way :- I think that if you make scenario, then it should send all comands specified separately. So I think if you examine DCERouter logs carefully, you'll probably see (or not) difference between command for Weeder light send separately or in group with other lights. You can tail that log in live fashion and examine it...

The specific light is named "Canale A - Lampada blu / Soggiorno" (Channel A - Blue Lamp / Living Room), and to me it looks like the lines in both cases (general and specific scenarios) are identical.If so the same 193 command should be issued to specific device in both cases, but this is not happening.

At this point I am clueless.Up to .40 this very same config was working fine, I noticed this issue with .41 but as I went for a fresh install I thought it may be my mistake in rebuilding devices.Now with .42 I made again step by step the whole config (reading it from my own wiki post ... thanks Rob for convincing me to post there ... ) so I'm 100% sure that config is correct.

you can also check things by manually send commands from web-admin page ('send command') on the device page....

Is it possible that maybe sending more commands in a row breaks some kind of timeout on controller (maybe it cannot receive commands one after another).... Nothing else comes to my mind, except that you carefully examine logs of automation controller (if it received commands, etc...)

I have similar behaviour from my IO board which I attribute to faulty soldering (it is a Velleman DIY board). Whne using the test tool, some functionality works (like manually switching single ports or "switch all on"), yet "switch all off" misses one port.

Don't want to say for sure this is your issue as well, but suggest it may be useful to evaluate whether this problem could be with a particular port on your weederboard (or whatever IO board you use), and not with Plutohome.